1. Page #
Name
Date
Points
My Points 82
Notes 8.1
2/26 15 83
Notes 8.2
3/4 84
Notes 8.2 presentation
3/6 10 85
8.2 review

2. 8.2 Two types of reproduction
Asexual reproduction is reproduction that requires only one parent.
Most single-celled organisms like bacteria and protozoans reproduce this way.
Sexual reproduction is a type of reproduction that involves special types of cells called sex cells.
Preview Questions
Why do you have characteristics of both parents?

3. 8.2 Chromosomes
Sex cells contain half the number of chromosomes as body cells (all of the other cells in a multicellular organism).
Human body cells have 46 chromosomes.
Human sex cells have 23 chromosomes.
Review – Which parent determines the child’s gender?

4. 8.2 Chromosomes
Meiosis is cell division that produces sex cells with half the number of chromosomes.
Meiosis is not a cycle.

5. 8.2 What happens in meiosis?
The events in meiosis are smooth and continuous:
Chromosomes double and thicken.
Nuclear membrane disappears.
Homologous chromosomes line up a the cell’s center.
Spindle fibers attach.
The nuclear membrane reforms.
Two cells form that are identical and diploid.

6. 8.2 What happens in meiosis?
In the second division, the chromosomes do not double.
Chromosomes thicken and line up at cell’s center.
Spindle fibers attach.
Chromosomes are pulled to opposite side of cell by spindle fibers.
Four new cells form when the nuclear membranes reform and cells separate.
The four new cells are unique and haploid so they have half the number of chromosomes compared to starting cells.

8. 8.2 Diploid, haploid and fertilization
A complete set of chromosomes is called a diploid set.
A half set of chromosomes is called a haploid set.
Most animal cells have a diploid set of chromosomes except in sex cells.
What is an easy way to remember haploid?

10. 8.2 Specialized cells
An embryo is an organism in its earliest stages of development.
A multicellular organism ends up with many different types of specialized cells.
All of those cells can be traced back to the zygote.

11. 8.2 Cell differentiation
Cell differentiation is the process of cell specialization.
As cells differentiate, they give rise to different tissues.
These tissues eventually form the organs.
How many cells do zygotes come from?